1. Field of the Invention
This invention relates to machines for applying labels to containers and in particular to applying sealing labels over pouring spouts on containers.
2. Description of the Prior Art
The need to install tamper indicating means on packages has been highlighted by the relatively recent intentional contamination of TYLENOL, and other non-prescription drugs and consumable products. For dry granular items such as bread crumbs, salt, or other fine powders that are dispensed from boxes or containers, one of the favorite methods of dispensing such granular material is by means of a retractable pouring spout that has been fastened to the box.
Machines for inserting spouts into the tops and sides of containers are known. A spout, generally, is placed in a container after it is filled. This makes handling such containers difficult in that any tipping of the container after it is filled and prior to insertion of the spout will result in spilling of material from the container along the production line.
Whether the spout is placed in the container before or after it is filled, insertion of such spouts requires synchronization between filling of the containers, delivery of the container to the insertion station, insertion of spouts therein, speed of the assembly line, etc. Examples of spout inserting machines are described in U.S. Pat. Nos. 4,072,117; 3,690,223; 3,523,512; 3,385,248; 3,381,645; and 4,583,899. The disclosures of all of these patents are incorporated herein by reference.
A problem associated with such spouts is that they are easily tampered with. There is no means by which it can be determined if the spout itself has been opened, other than by providing an overlay on the spout. It is important that such an overlay be positioned exactly on the spout, because if it is not then a contaminant may still be poured into the container through the spout. Thus, the positioning of the overlay label is critical. The label must also not be removable, thus requiring the sealing label to be broken in order to open the spout. A broken sealing label will thus indicate that there has been tampering with the spout.
A known method for sealing spouts is by using a continuous wrapping, e.g. cellophane, to enclose the entire container. For containers which have a spout located on the flat top of the container, a label can be used. In the case of a container with a spout positioned on the side, however, difficulties arise in exactly positioning a sealing label over the spout due to seams, decorations, artwork, etc.
The exact positioning of a label in relation to the spout can be important in maintaining a seal to insure the usefulness of the product therein. For example, in containers which have water sensitive material such as soaps or detergents a label which overlays the spout so as to hermetically seal the spout opening is advantageous in extending the shelf life of the material in the container. The prevention of moisture from entering the container will enable the material to stay in the box without caking or otherwise absorbing the material.
Further, as is often the case in the retail trade, containers having pouring spouts are often stacked one on top of the other. Such stacking tends to crush or distort the containers. By placing a label over the spout it prevents the spout from being forced open by such crushing thereby preventing spilling of the materials from the containers while also making the material in the individual containers less vulnerable to contamination.